Byron Roe's Homepage


355 W. Hall; Phone (734)764-4441; > byronroe@umich.edu
Last modified: Mon. March 6, 2017

Research interests

My major research interests are in the field of particle physics.

I have been working on Fermilab experiment, mini-BooNE (Booster Neutrino Experiment) for about 20 years. I supplied monitoring counters for the experiment, contributed to the neutrino flux program, wrote one of three event reconstruction programs, and introduced the new technique of boosted decision trees into MiniBooNE (and physics generally). This technique was used as the basis for one of our two oscillation analyses. MiniBooNE has measured a number of neutrino cross sections in the energy range below about 2 GeV with about two orders of magnitude more events than any previous experiment. It originally was searching for a small sterile neutrino mass by looking for oscillations of muon neutrinos into electron neutrinos The Los Alamos Neutrino Detector (LSND) reported a possible signal. A few years ago we published a result supporting the LSND signal at about the 3.5 standard deviation level. With further data we published a PRL letter in 2018 which confirms this result at the 4.7 standard deviation level using both neutrino and anti-neutrino data. If the LSND results are included the signal is at the 6 standard deviation level,

For a few years we ran in a beam dump mode searching for sub-GeV dark matter particles. In 2018 we published a PRL article based on neutral current-like events which puts further constraints on limits for these particles, and rules out most of the area that might have contributed to the g-2 discrepancy. We are in the final stages of publishing results for two other channels (electron-like and pi0-like) which should be even more sensitive.

In 2017 I worked on some studies for the DUNE experiment. In particular, I have calculated the density of earth as a function of distance of neutrinos from the starting point at Fermilab to the ending point at Sanford Lab, some 1285 km away. I have also examined whether it is necessary to use a variable density program or whether one can use an average density. It appears that for the checks I have made that the average of the variable densities seems to work well. The results were published in a Physical Review article in 2017. For those who wish to work further, the 12 basic files used for this test (variable density, density = 2.848 gm/cm^3, and density = 2.957 gm/cm^3 Files for both CP conserving and delta = 1.5pi CP non-conserving. for nu and nubar can be downloaded below. Var refers to variable density using the shen map. The various fixed densities are noted below. Mu refers to neutrinos (negatively focussed beam) and mubar refers to anti-neutrinos. Each file has four columns corresponding to energy (GeV), Pr(nu_e), Pr(nu_mu), and Pr(nu_tau). There are 4000 energies chosen with equal logarithmic intervals between 0.05 and 20 GeV.

The next files are the basic files from my DUNE oscillation studies

nu, noCP viol., variable density

nu, noCP viol, 2.848 fixed rho

nu, noCP viol, 2.957 fixed rho

nu, CP viol., variable density

nu,CP viol, 2.848 fixed rho

nu, CP viol, 2.957 fixed rho

nubar, noCP viol., variable density

nubar, noCP viol, 2.848 fixed rho

nubar, noCP viol, 2.957 fixed rho

nubar, CP viol., variable density

nubar,CP viol, 2.848 fixed rho

nubar, CP viol, 2.957 fixed rho

Pedagogy

I have written two graduate textbooks.

Page of gif and other picture files: Gif and other files

Boosting talk 2005

The next file is the gzipped tar file for the C++ version of my boost program. The latest modification is May 8, 2007 and contains important improvements and bug fixes, including an error that prevented softscore from working on data. If you copy this file, please e-mail me at byronroe@umich.edu so that I can notify you of important changes. This is the tar file for the C++ version of m-boost.

The next file is the gzipped tar file for the FORTRAN version of my boost program. The latest modification is May 8, 2007 and fixes a bug in the data_loop_over_trees routine. The February 17, 2007 contains important improvements and bug fixes, including an error that prevented softscore from working on data. If you copy this file, please e-mail me at byronroe@umich.edu so that I can notify you of important changes. This is the tar file for the FORTRAN version of m-boost

This link is for a file of events and background for the Banff meeting (2006). The file is a formatted file. In the first line is the the number of signal events followed by the number of background events. The signal events come first, followed by the background events. Each line, after the first line has the 50 particle ID variables for one event. 50 variable data file